This invention relates to a printed wiring board and more particularly to an improved board which is used for connecting electronic and electric devices thereto.
It is well known to use polyester sheets as board materials and to provide wiring patterns by printing silver or carbon paste on the board or by applying etching to an aluminum evaporation layer.
FIGS. 3 and 4 show conventional connectors employing the polyester sheets.
The polyester sheets have poor characteristics with respect to heat-resistance and soldering, so that as illustrated in FIG. 3, an electronic device 83 is usually connected to a printed wiring board 8 through hole 81 formed therein. A wiring pattern 82 extends through the hole 81 to the back surface 82' of the board 8 where the terminal 84 of the electronic device 83 inserted into the hole 81 is soldered to the pattern 82.
In this structure, however, the printed wiring board is required to have its both sides printed, which leads to high manufacturing cost compared to one side printed board. To solve such a problem, there is proposed a printed wiring board 9 which has two holes 91 and 92 adjacent to each other as shown in FIG. 4. The terminal 94 of an electronic device 93 is inserted in the hole 91 and then is folded so as to be inserted again in the hole 92, projecting out of the front surface 95 of the board 9 in such a manner that the end of the terminal 94 is soldered to a wiring pattern. Such a prior art device, however, requires a number of laborious processes of providing the holes in the board 9 and folding the terminal 94.
It is therefore an object of this invention to provide a printed wiring board which completes electrical connection without soldering.
It is a further object of this invention to provide an improved board which completes electrical connection by means of the restoring force of a resilient sheet.